Microbicidal slimicide compositions for industrial use

ABSTRACT

There disclose stable and non-aqueous microbicidal compositions which are useful for controlling slime in pulp and paper manufacturing processes and industrial cooling water systems and which comprise 4,5-dichloro-1,2-dithiol-3-one as the active ingredient, and specific surfactants and hydrophilic organic solvents.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to microbicidal compositions for industrial use,and in particular to slime controlling compositions to be used in pulpand paper manufacturing processes and in industrial cooling watersystems, in other words, compositions useful as microbicidalcompositions to be used in water systems.

2. Description of the Prior Art

The active ingredient of the compositions of the present invention,namely 4,5-dichloro-1,2-dithiol-3-one, is known to have potentbactericidal and fungicidal activities (Japanese Patent Publication No.14294/1977). Since this compound is hardly soluble in water, however,compositions in which said compound is made soluble in water arerequired in order that the compound may be utilized as slime controllingagent in paper manufacturing processes and in industrial cooling watersystems. Consequently some compositions have been proposed which employas surfactant a specific quaternary ammonium salt or a specificpyridinium salt (Japanese Patent Application Laid-Open No. 82723/1976).However, the compositions shown therein by way of examples contain saidsurfactant in an amount 2.5-5 times as much as that of the activeingredient and that in a water-containing solvent.

There are also known aqueous or nonaqueous compositions wherein aspecific quaternary ammonium salt is added in an amount approximatelyequal to that of a certain active ingredient (methylenebisthiocyanate)which is effective as slime controlling agent useful also in papermanufacturing processes, in expectation of bactericidal activity of saidammonium salt itself (cf. Japanese Patent Publication No. 10927/1975 andNo. 21319/1970); and aqueous or nonaqueous compositions includingslimicidal ones, wherein nonionic surfactants are added in amountsalmost equal to or smaller than those of active ingredients (cf.Japanese Patent Publications Nos. 23897/1973, 23902/1973, 38848/1973 and21319/1970).

Whereas, as mentioned above, slime controlling compositions for use inpaper manufacturing processes should desirably be water-soluble, theactive ingredient may be water-insoluble but then the active ingredientis required to be capable of being well dispersed in the form of minuteparticles. It is of course required that the slime controllingcomposition should not be corrosive against the machinery, not adverselyaffect paper in respect of properties thereof, such as sizing degree,brightness, strength, color, etc., and not do any such harm topapermaking as decrease in freeness or in yield. what is more importantis that the composition, when used at a necessary concentration, shouldnot cause any foaming. The compositions for use in cooling watersystems, too, are naturally required not to cause bubble formation andto have minimal adverse effect on the machinery.

DETAILED DESCRIPTION OF THE INVENTION

The present inventors have conducted intensive research on thepreparation of compositions containing 4,5-dichloro-1,2-dithiol-3-onehaving the formula: ##STR1## and have now succeeded in making novel andstable nonaqueous compositions.

The compositions of the present invention do not use water as solvent,but contain specific surfactants selected from among a very wide rangeof surfactants, and the compositions themselves are very stable.Moreover, the compositions, when used in water systems, allow the activeingredient to be dispersed in a very satisfactory manner so that it canshow its bactericidal and fungicidal activities to the fullest. Inaddition, the amount of said specific surfactants to be added isextremely small from a common-sense standpoint, and therefore no foamingproblem may arise from the addition of the surfactants. Furthermore, thecompositions of the invention have such an advantage that the usethereof does not adversely affect the properties of paper.

Thus, according to the present invention, there are provided stablemicrobicidal compositions for industrial use which comprises 3-20 partsby weight of 4,5-dichloro-1,2-dithiol-3-one as active ingredient, atleast 0.2 part by weight per 10 parts by weight of said activeingredient of a surfactant selected from the group consisting of N, N,N', N'-polyoxyethylene polyoxypropylene-ethylenediamines andalkylolamide type nonionic surfactants, and a sufficient amount of ahydrophilic organic solvent to make 100 parts by weight of thecomposition, said composition being substantially free from water.

The amount of the active ingredient, 4,5-dichloro-1,2-dithiol-3-one, in100 parts by weight of the whole composition is generally 3-20,preferably 5-15, and more preferably 8-12 parts by weight. If the amountis excessively large, a crystalline precipitate may separate out duringblending, storage or use. Conversely, if the amount is too small, theresulting composition will be disadvantageous from an economicalstandpoint.

"N, N, N', N'-polyoxyethylene polyoxypropylene-ethylenediamines" as usedin the invention can be expressed as ethylenediamine adducts of ethyleneoxide-propylene oxide block copolymers, which are surfactants and may beprepared by reacting ethylenediamine with propylene oxide and reactingthe resultant with ethylene oxide in accordance with the conventionalmethod. Such surfactant may be represented by the following formula:##STR2##

TETRONICS ® (Wyonddotte Chemical Corp., U.S.A.) and TETRONIC® (AsahiDenka Kogyo K.K.) are mentioned as commercially available products ofsaid surfactant.

In practicing the invention, a wide variety of N, N, N',N'-polyoxyethylene polyoxypropylene-ethylenediamines having variouslydifferent molecular weights, HLB (hydrophilic lipophilic balance)values, forms and other characteristics depending on the amountsspecified as desired of ethylene oxide and propylene oxide addedrespectively and on the manner of combination of these can be used.Generally, however, those wherein the total molecular weight of thepropylene oxide units is about 2,000-27,000 and the ethylene oxide unitcontent is 10-80 percent by weight based on the whole molecule are used.

The term "alkylolamide type nonionic surfactants" as used herein meansfatty acid alkylolamides synthesized from fatty acids and alkylolamines.Preferred are the alkylolamides obtained by reaction of higher fattyacids having 8-18 carbon atoms and ethanolamine or diethanolamine. Thosethat are soluble in water are recommendable. Especially preferred fattyacid alkylolamides are those obtained by reaction of one mole of coconutoil fatty acid (a mixture of higher fatty acids derived from coconutoil) with one or two moles of diethanolamine. As commercially availableproducts there are mentioned CONCENSATE P.A® (Continental Chemical Co.,U.S.A.), STATOAMF® (Nippon Oil & Fats Co., Ltd., Japan) and PROFAN®(Sanyo Chemical Ind. Ltd., Japan).

The amount of the surfactant specified herein and to be added is atleast 0.2 part by weight per 10 parts by weight of the activeingredient, or at least 0.006 percent by weight based on the wholecomposition. The amount is generally 0.3 part by weight or more per 10parts by weight of the active ingredient. In the case of an ethyleneoxide-propylene oxide block copolymer-ethylenediamine adduct 0.3-1.0part by weight thereof is preferred and in the case of an alkylolamidetype nonionic surfactant 0.3-3.0 parts by weight thereof are preferred,per 10 parts by weight of the active ingredient. Sometimes thesurfactant may amount to 2-8 parts by weight on the same basis. Largeramounts, though generally favorable for the active ingredient to bedispersed well in the organic solvent, are unfavorable because ofpossible foaming at the time of use.

It is essential that the hydrophilic organic solvent to be usedaccording to the present invention is capable of dissolving the activeingredient as well as compatible or miscible with water, that, when usedwith the surfactant specified herein, said solvent gives a stablecomposition, and that, when the composition is added to water, saidsolvent facilitates dispersion of the composition. Suitable examples ofthe hydrophilic organic solvent are amides (dimethylformamide anddiethylformamide), ethers (methyl cellosolve, ethyl cellosolve, phenylcellosolve and diethylene glycol monomethyl ether), alcohols and glycols(isopropyl alcohol, diethylene glycol, dipropylene glycol andpolypropylene glycol) and ketones (acetone and methyl isobutyl ketone).Combined use of two or more of these is possible. Among others arepreferred, in view of stability of the resulting composition which alsocontains the surfactant and good dispersibility noted when thecomposition is added to water, dimethylformamide, methyl cellosolve,phenyl cellosolve, polyethylene glycol, diethylene glycol, diethyleneglycol monomethyl ether and dipropylene glycol. In each case, the mostpreferable is dimethylformamide alone or in combination with one or moreof the preferable solvents mentioned above.

These hydrophilic organic solvents may be of industrial grades. That isto say, they need not be absolutely anhydrous, but should be used in asubstantially anhydrous state. Of course, water is never added to thecomposition.

The hydrophilic organic solvent generally amounts to less than about 95percent by weight based on the composition.

In preparing the compositions of the present invention, conventionalmethods of dissolution and blending can be employed. Thus, for example,the active ingredient is dissolved in the hydrophilic organic solventwith stirring, and then, to the resulting solution, the surfactantspecified herein is added, followed by stirring to yield a homogeneouscomposition. The order of dissolutions or blendings can naturally bereversed.

The composition of the present invention is used at concentrationsdepending upon the kind of industrial water (process water in paper andpulp making, cooling water, washing water, etc.), the state of attachingslime, the kinds of slime-forming bacteria, fungi and yeasts, etc..Generally, concentrations of 5-50 ppm (the concentrations of the activeingredient being 0.25-10 ppm) are sufficient to inhibit the growth ofmicroorganisms. In cases where bactericidal and fungicidal effects areto be achieved, the composition is used at concentrations of 10-100 ppm,preferably 30-50 ppm, with success.

More specifically, in paper making process, the composition of thepresent invention is added to the stuff box, the stock part of machinechest or the circulating part of white water in save-all, by aconventional continuous or impact feeding method. For instance, theimpact feeding is conducted once to three times per day, taking 30 or 60minutes per dosing. In cooling water system, the composition is added toe.g., the cooling pit, once with one portion for one to ten days in aquantity which gives an effective concentration for the total coolingwater. Also, the composition can be added to the pulp slurry which isstored during stop of operation of paper making machine. In this case,the composition is dosed in one portion and in a quantity which issufficient to give a necessary effective concentration.

The following examples will illustrate the invention more in detail.

EXAMPLES 1-24 and COMPARATIVE EXAMPLES 1-4

Various compositions were prepared according to the recipes specified inTables 1 and 2 and following the procedure described hereinafter, andexamined for their stability, dispersibility in water and foamingability.

Thus, 4,5-dichloro-1,2-dithiol-3-one is dissolved in a solvent, and asurfactant is added in specified amounts. One hundred microliters (100μl) of the resulting composition was pipetted and added dropwise to 100cc of water in a glass colorimetry cell 25 mm in diameter and 300 mm inheight. The stage in which the test composition was emulsified anddispersed in water was observed. After completion of the dropping, themixture was shaken vigorously for 30 seconds and then allowed to stand,and the foaming power was evaluated in terms of the height of theremaining foam.

                                      TABLE 1                                     __________________________________________________________________________    Case where polyoxyethylenepolyoxypropylene-ethylenediamines were used as      surfactants.                                                                                  (Parts by weight)                                                             Solvent                                                                                                    Diethylene                           Active                  Poly-            glycol                           Exam-                                                                             ingre-      Dimethyl                                                                            Diethylene                                                                          ethylene                                                                           Methyl                                                                              Phenyl                                                                              monoethyl                        ple dient                                                                             Surfactant                                                                            formamide                                                                           glycol                                                                              glycol                                                                             Cellosolve                                                                          Cellosolve                                                                          ether                            __________________________________________________________________________    1   10.0     0.5                                                                              89.5  --    --   --    --    --                                       M.W.                                                                  2   5.0 3700 1.5                                                                              93.5  --    --   --    --    --                                       E.O.                                                                  3   15.0                                                                              30 wt %                                                                            0.75                                                                             84.25 --    --   --    --    --                               4   20.0     1.0                                                                              79.0  --    --   --    --    --                                       M.W.                                                                  5   10.0                                                                              3700 0.5                                                                              5.0   84.5  --   --    --    --                                       E.O.                                                                  6   10.0                                                                              10 wt %                                                                            0.5                                                                              5.0   --    84.5 --    --    --                                       M.W.                                                                  7   10.0                                                                              3700 1.0                                                                              --    --    --   89.0  --    --                               8   10.0     0.5                                                                              --    49.5  --   40.0  --    --                                       E.O.                                                                  9   10.0                                                                              20 wt %                                                                            0.5                                                                              --    --    49.5 40.0  --    --                                       M.W.                                                                  10  10.0                                                                              3700 1.0                                                                              50.0  --    --   39.0  --    --                                       E.O.                                                                  11  10.0                                                                              40 wt %                                                                            1.0                                                                              --    --    --   39.0  50.0  --                                       M.W.                                                                  12  10.0                                                                              4000 0.5                                                                              --    --    --   --    89.5  --                               13  10.0     0.5                                                                              --    39.5  --   --    50.0  --                                       E.O.                                                                  14  10.0                                                                              80 wt %                                                                            0.5                                                                              --    --    39.5 --    50.0  --                                       M.W.                                                                  15  5.0 6700 0.5                                                                              --    --    --   --    --    94.5                                     E.O.                                                                  16  7.0 10 wt %                                                                            0.5                                                                              --    --    --   --    --    92.5                             Comparative                                                                           M.W.                                                                  1   25.0                                                                              6700 1.0                                                                              74.0  --    --   --    --    --                                       E.O.                                                                  2   25.0                                                                              10 wt %                                                                            10.0                                                                             65.0  --    --   --    --    --                               __________________________________________________________________________     Notes:                                                                        M.W. means the molecular weight of the hydrophobic portion (propylene         oxide portion) in the polyoxyethylene polyoxypropyleneethylenediamine, an     E.O. means the proportion (weight percent) of the ethylene oxide portion      to the whole molecule of said surfactant.                                

                                      TABLE 2                                     __________________________________________________________________________    Cases where coconut oil fatty acid diethanolamides were used as               surfactants.                                                                                (Parts by Weight)                                                             Solvent                                                                                                    Diethylene                             Active                Poly-            glycol                             Exam-                                                                             ingre-    Dimethyl                                                                            Diethylene                                                                          ethylene                                                                           Methyl                                                                              Phenyl                                                                              monoethyl                          ple dient                                                                             Surfactant                                                                          formamide                                                                           glycol                                                                              glycol                                                                             Cellosolve                                                                          Cellosolve                                                                          ether                              __________________________________________________________________________    17   5  1.0*  94    --    --   --    --    --                                 18  10  1.0** 89    --    --   --    --    --                                 19  20  3.0** 77    --    --   --    --    --                                 20  10  1.0**  5    84    --   --    --    --                                 21  10  1.0*  20    --    69   --    --    --                                 22  10  1.0** 50    --    --   39    --    --                                 23   5  1.0*  --    84    --   --    --    --                                 24   5  1.0** --    94    --   --    --    --                                 Comparative                                                                   3   25  1.0*   74   --    --   --    10    --                                 4   25  10.0**                                                                              65    --    --   --    --    --                                 __________________________________________________________________________     Notes:                                                                        *denotes 1:1 type, i.e. reaction product of coconut oil fatty acid with       diethanolamine in a molar ratio of 1:1, product of Sanyo Chemical             Industries, Ltd., "Profan 1281" by trade name.                                **denotes 1:2 type, i.e. reaction product of coconut oil fatty acid with      diethanolamine in a molar ratio of 1:2, product of Sanyo Chemical             Industries, Ltd., "Profan 1281 Extra" by trade name.                     

The compositions of Examples 1-24 shown in the above tables all wererapidly dispersed in water in an emulsified state after addition,presenting a uniform and good dispersion state in a short time. On thecontrary, the compositions of Comparative Examples 1-4 upon additioncaused precipitation of fine crystals of 4,5-dichloro-1,2-dithiol-3-one,and never gave uniform dispersions.

Concerning the forming phenomenon, such a phenomenon could not beobserved at all with the compositions of Examples 1, 3-6, 8, 9, 12-14,16, 18, 20, 22 and 24 and of Comparative Example 3. The compositions ofExamples 2, 7, 10, 11, 15, 17, 19, 21 and 23 and of Comparative Example1, when shaken, formed foam, but the foam, on standing, disappearedimmediately. In the cases of Comparative Examples 2 and 4, foam remainedand had a height of about 10 mm even after 15 seconds of standing.

Furthermore, the compositions of Examples 1-24 could be stored for morethan 3 months without any change in their good state of dispersion; notendency was noted toward separation or precipitation of crystals or thelike.

EXAMPLES 25-26

The microbicidal compositions of Examples 3 and 21 were each tested tosee their possible influence on the properties of paper.

A pulp was beaten according to the method employed in JIS P 8210 and thepulp concentration adjusted to 3%. A size ("SizePine E" by trade name,product of Arakawa Kagaku Kogyo K.K.) was added in an amount of 0.5% (assolid) based on the pulp, and the pH adjusted to 4.0 with aluminumsulfate. After 5 minutes of stirring and 10-fold dilution with water,the microbicidal composition was added so that each concentrationspecified in Table 3 might be attained. After standing for 5 minutes,paper specimens were made according to JIS P 8209 and tested for theirproperties by the conventional methods. The results are shown in Table3.

                                      TABLE 3                                     __________________________________________________________________________                  Bright-                                                                           Breaking                                                                           Bursting                                                                           Folding                                                                             Tearing                                                                            Sizing                                        Test method                                                                          ness                                                                              length                                                                             strength                                                                           endurance                                                                           strength                                                                           degree                                        Concen-                                                                              JIS JIS  JIS  JIS   JIS  JIS                                           tration                                                                              P 8123                                                                            P 8113                                                                             P 8112                                                                             P 8115                                                                              P 8116                                                                             P 8122                                 Composition                                                                          (ppm)  (%) (km) (kPa)                                                                              (times)                                                                             (mN) (sec)                                  __________________________________________________________________________    Example 3                                                                             0     81.5                                                                              4.76 3.00 780   54.0 12.5                                          10     81.5                                                                              4.70 2.96 760   53.3 12.3                                          50     81.0                                                                              4.65 3.05 780   53.9 12.6                                          100    81.8                                                                              4.75 3.02 780   53.9 12.0                                   Example 21                                                                            0     80.4                                                                              3.28 2.20 940   41.6 12.6                                          10     80.1                                                                              3.76 2.20 880   48.0 12.2                                          50     80.4                                                                              3.76 2.21 900   44.8 12.4                                          100    80.6                                                                              3.78 2.28 1000  41.6 12.1                                   __________________________________________________________________________

It is clear from the results in Table 3 that the compositions ofExamples 3 and 21 have no influence upon the properties of paper at aconcentration as high as 100 ppm. Foaming was never promoted by theaddition of the compositions of the present invention.

EXAMPLES 27-28

In a certain paper mill, in the white water circulating system of apaper machine for making wood free paper, especially on the deflectorunder the wire cloth, on the walls of the seveall and on the walls ofthe drum screen, pink slime mainly composed of Flavobacterium specieswas formed in large quantities, and a great number of pink spotsappeared on the paper surface. In a short time, this made it necessaryto do washing with water or a bleaching liquor. Here, after the washing,either of the microbicidal compositions of Examples 1 and 20 wasinjected into the flow of stock suspension in the machine chest forconsecutive 8 hours daily so that a concentration of 10 ppm might beobtained. By these additions, pink slime formation was completelystopped, and spots on the product then hardly appeared. Naturally, theaddition of the compositions of the invention did not cause foaming.

EXAMPLE 29

The following test was made in a petrochemical plant equipped with acooling tower system in which 400 tons of water was under circulation ata rate of 2,000 tons/hour.

The composition of Example 14 was added to the circulating water nearthe intake of the cold water pit so that a concentration of 50 ppm mightresult in said system. The addition caused decrease in number ofbacteria from 5.0×10⁶ /ml before the addition to 1.0×10² /ml after theaddition. One week later, slime was no more formed, accordingly thecooling efficiency hardly decreased but the number of bacteria amountedto 1.0×10⁶ /ml. Therefore, the same composition was again added to aconcentration of 50 ppm. Thereafter the addition of 50 ppm was repeatedat hourly intervals for 3 months. Any trouble at least due to slimeformation, such as choking or blocking of the heat exchanger or decreasein cooling efficiency, did not arise at all.

EXAMPLE 30

A test similar to that of Example 29 was made in a petrochemical plantequipped with a cooling tower system in which 300 tons of water wasunder circulation at a rate of 2,000 tons/hour.

The composition of Example 20 was added to the circulating water nearthe intake of the cold water pit so that a concentration of 50 ppm mightresult in said system. The addition caused decrease in number ofbacteria from 6.0×10⁵ /ml before the addition to 2.0×10² /ml after theaddition. One week later, slime was no more formed, accordingly thecooling efficiency hardly decreased, but the number of bacteria amountedto 1.0×10⁶ /ml. Therefore, the same composition was again added to aconcentration of 50 ppm. Thereafter the addition of 50 ppm was repeatedat hourly intervals for 3 months. Any trouble at least due to slimeformation, such as choking of the heat exchanger or decrease in coolingefficiency, did not arise at all.

What is claimed is:
 1. A stable microbicidal slimicide composition forindustrial use which comprises 3-20 parts by weight of4,5-dichloro-1,2-dithiol-3-one as active ingredient, at least 0.2 partby weight per 10 parts by weight of said active ingredient of asurfactant selected from the group consisting ofN,N,N',N'-polyoxyethylene polyoxypropylene-ethylenediamines andalkylolamides type nonionic surfactants, and a sufficient amount of ahydrophilic organic solvent consisting essentially of a solvent selectedfrom the group consisting of dimethylformamide, methyl cellosolve,phenyl cellosolve, diethylene glycol, dipropylene glycol, diethyleneglycol monomethyl ether, and mixtures thereof to make 100 parts byweight of the composition, said composition being substantially freefrom water.
 2. The composition of claim 1, wherein said hydrophilicorganic solvent is dimethylformamide.
 3. The composition of claim 1,wherein said hydrophilic organic solvent is diethylene glycol monomethylether.
 4. The composition of any one of claims 1, 2 or 3, wherein saidpolyoxyethylene polyoxypropylene-ethylenediamine is present in an amountof 0.3-1.0 part by weight per 10 parts by weight of said activeingredient.
 5. The composition of any one of claims 1, 2 or 3, whereinsaid polyoxyethylene polyoxypropylene-ethylenediamine is present in anamount of 0.5-1.0 part by weight per 10 parts by weight of said activeingredient.
 6. The composition of any one of claims 1, 2 or 3, whereinsaid alkylolamide type nonionic surfactant is present in an amount of0.3-3.0 parts by weight per 10 parts by weight of said activeingredient.
 7. The composition of any one of claims 1, 2 or 3, whereinsaid alkylolamide type nonionic surfactant is present in an amount of0.5-2.0 parts by weight per 10 parts by weight of said activeingredient.
 8. The composition of any one of claims 1, 2 or 3, whereinsaid active ingredient is present in an amount of 8-12 parts by weightper 100 parts by weight of said composition.
 9. The composition of anyone of claims 1, 2 or 3, wherein said active ingredient is present in anamount of 10 parts by weight per 100 parts by weight of saidcomposition.
 10. The composition of claim 1, wherein said alkyloamidetype nonionic surfactant is a fatty acid diethanolamide.
 11. Thecomposition of claim 10, wherein said fatty acid diethanolamide is aproduct of the reaction of one mole of a fatty acid and one or two molesof diethanolamine.
 12. The composition of claim 11, wherein said fattyacid diethanolamide is a product of the reaction of one mole of coconutoil fatty acid with one or two moles of diethanolamine.
 13. In a methodfor controlling slime formation in wood pulp or paper manufacture,having a water system the improvement comprising adding a slimicidecomposition to said water system which is composed of 3-20 parts byweight of 4,5-dichloro-1,2-dithiol-3-one as active ingredient, at least0.2 part by weight per 10 parts by weight of said active ingredient of asurfactant selected from the group consisting ofN,N,N',N'-polyoxypropylene polypropylene-ethylenediamines andalkylolamides type nonionic surfactants, and a sufficient amount of ahydrophilic organic solvent consisting essentially of a solvent selectedfrom the group consisting of dimethylformamide, methyl cellosolve,phenyl cellosolve, diethylene glycol, dipropylene glycol, diethyleneglycol monomethyl ether, and mixtures thereof to make 100 parts byweight of the composition, said composition being substantially freefrom water.